Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual Open 2nd VIII teve um U15 6th Quad da BGS e um U16 1st VII da TSS?
 ###Tabelas: CREATE TABLE biggest_wins (biggest_wins_id AUTO_INCREMENT PRIMARY KEY, Margin INT, Score VARCHAR, Opponent VARCHAR, Venue VARCHAR, Date VARCHAR) CREATE TABLE fourth_round (fourth_round_id AUTO_INCREMENT PRIMARY KEY, Tie no INT, Home team VARCHAR, Score VARCHAR, Away team VARCHAR, Attendance INT) CREATE TABLE 2010s_49ers_3-2-1 (2010s_49ers_3-2-1_id AUTO_INCREMENT PRIMARY KEY, Year INT, Date VARCHAR, Home Team VARCHAR, Result VARCHAR, Visiting Team VARCHAR, Venue VARCHAR) CREATE TABLE winning_head_of_the_river_championship_events (winning_head_of_the_river_championship_events_id AUTO_INCREMENT PRIMARY KEY, Crew INT, Open 1st VIII VARCHAR, Open 2nd VIII VARCHAR, Open 3rd VIII VARCHAR, U16 1st VIII VARCHAR, U16 2nd VIII VARCHAR, U16 3rd VIII VARCHAR, U15 1st Quad VARCHAR, U15 2nd Quad VARCHAR, U15 3rd Quad VARCHAR, U15 4th Quad VARCHAR, U15 5th Quad VARCHAR, U15 6th Quad VARCHAR) CREATE TABLE type_i (type_i_id AUTO_INCREMENT PRIMARY KEY, Part Number VARCHAR, Pins VARCHAR, Body Width/mm INT, Body Length/mm INT, Lead Pitch/mm INT)  
SELECT Open 2nd VIII FROM winning_head_of_the_river_championship_events WHERE U15 6th Quad = bgs AND U16 1st VIII = tss